As explained in the Armstrong U.S. Pat. No. 1,965,758, issued July 10, 1934 and in the Bratton U.S. Pat. No. 3,127,459, issued Oct. 5, 1965, it is frequently desirable that bricks and other similar products formed from compressed refractory material include at least one central bore or aperture. As also stated in those patents, while one method of forming a hole in the bricks is to pour granular refractory material into a press cavity having a stationary internal mandrel or core and then compressing that refractory material, the bricks produced by this process are frequently subject to breakage because it is difficult to successfully compact the granular refractory material around the central mandrel. It is preferred that the refractory material be poured into the mold cavity whereupon the core or mandrel is then forced through the granular refractory material to form the desired bore or indentation. The latter procedure produces refractory products having improved strength and resistance to fracture.
As also explained in U.S. patent application Ser. No. 965,794, filed Dec. 4, 1978 by Dorsey and titled "Press for Compressing Refractory Material and Including a Quick Change Mold Box", and assigned to the assignee of the present invention, and in the Dorsey U.S. Pat. No. 3,447,205, issued June 3, 1969, it is desirable that the brick press be constructed so as to include a mold box which is supported in such manner that it is readily removable from the press to thereby facilitate repair of the mold box or substitution of an alternative mold box to thereby permit manufacture of other types or sizes of bricks. Accordingly, it is desirable that any means provided for forming the desired bores or indentations in the pressed refractory products should not interfere with removal of the mold box.
Attention is also directed to the following prior art patents which illustrate various brick press constructions. See for example U.S. Pat. No. 3,210,450, the Collins U.S. Pat. No. 2,984,888, and the Campbell U.S. Pat. No. 2,723,436. Attention is further directed to the Locatelli U.S. Pat. No. 2,542,874, the Miller et al. U.S. Pat. No. 2,254,107, and the Eberling U.S. Pat. No. 1,543,068.